An Argo float (a French version called an Arvor) is being launched from a French research vessel called the “Pourquoi Pas?” or “Why Not?”. It is one of 3,800 such floats monitoring ocean temperature and salinity around the world. (Provided)

Free public lecture timed with scientific meeting in Sidney

Oceanographer Gregory Johnson speaks on the robots that monitor ocean temperature and salinity

If you sail, fish or farm, the characteristics of the ocean are relevant to you. Its saltiness, its temperature, and its direction of travel affect the year’s catch, your voyage time, or when the flowers bloom. Some of that data comes from about 4,000 floating probes in the ocean, known as Argo, and on the week of March 12, the international team of scientists responsible for it are converging on Sidney for their yearly meeting.

Oceanographer Gregory Johnson is giving a free public lecture at the Shaw Centre for the Salish Sea on March 15 to tell the public more about their work.

Howard Freeland, a scientist emeritus with the federal Institute of Ocean Sciences in North Saanich , said the public was a tradition started four years ago. Freeland was part of the original team that proposed Argo in 1999, and was on its steering committee for most of the 2000s. Though he is retired, he says he still does odd jobs for the project.

Freeland said it is not enough to study one portion of the ocean for many purposes, so Argo is dotted across the globe.

“We get heat content of the ocean everywhere, which dominates weather forecasting. If you’re forecasting El Nino, you must know the properties of the ocean everywhere,” said Freeland.

The floats primarily measure ocean temperature and salinity. The ocean temperature regulates weather on earth; without temperature readings, there are no accurate weather forecasts. Freeland said the reason we can predict the weather five or six days out is because of data provided by Argo. The data is, by oceanography standards, very real time. They get about 90 per cent of the data reported within 24 hours on one of two websites, where the data is available for anyone to download for free.

“A schoolchild in Saskatoon has the same right of access that I have.”

Freeland’s own interest in that is on how ocean temperatures change, and he said there is still much to learn.

“For a long time, we assumed that the all the warming of the ocean was taking place near surface… When you warm something, it expands; the ocean is no different,” he said.

Scientists discovered recently that the deep ocean is warming as well, though the mechanics are still being worked out.

Johnson, who is giving this year’s lecture, is leading the effort to get Argo into the very deep ocean, something it was not originally designed to do. The probes measure properties of the ocean at 2,000 metres below the surface and Johnson was part of the discovery that the abyssal waters (the deepest part of the ocean) are also warming. Johnson also summarized an entire 2,200-page IPCC climate report into 19 haiku poems, complete with watercolour paintings.

Freeland said over the years, he’s learned that there is “an insatiable public appetite for information about the earth, especially the ocean.”

The public lecture two years ago was done by Freeland himself in Sendai, Japan. “There was a huge audience. Lot of very young people,” including a 12-year old girl who asked a lot of questions. “I expect there will be a good audience for this talk.”

The free lecture takes place at the Shaw Centre for the Salish Sea in Sidney March 15 at 7 p.m., with doors at 6:30 p.m. Seating is limited.